return (str: string, regExStr: string, replaceValue: string) => {
   if (!isDefined(regExStr)) {
     $log.debug(`Did not supply regex string for 'replace' filter.`);
     return str;
   } else if (!isDefined(replaceValue)) {
     $log.debug(`Did not supply replacement value for 'replace' filter.`);
     return str;
   } else {
     return str.replace(new RegExp(regExStr, 'g'), replaceValue);
   }
 };

 function (event, unfoundState, fromState, fromParams) {
     $log.warn('$stateNotFound', {
         event: event,
         unfoundState: unfoundState,
         fromState: fromState,
         fromParams: fromParams
     });
 });

 const watchDocumentVisibility = (): void => {
   this.$log.debug('document visibilityState changed to: ', document.visibilityState);
   if (document.visibilityState === 'visible') {
     resumeScheduler();
   } else {
     suspendScheduler();
   }
 };

    loadMessage(): void {
        this.$log.info(`[${this.name}] Loading message...`, this);

        this.sampleService
            .getData()
            .then(this.onDataReceived.bind(this))
            .catch(this.handleError.bind(this));
    }

  // todo: add api storage
  updateInStorages(basket: IBasket): IPromise<IBasket> {
    const stored = this.storeBasketInLocalStorage(basket);

    if (!stored) {
      this.$log.error('Basket: Unable to store basket in local storage');
    }

    return this.fetchBasket();
  }

 const resumeScheduler = (): void => {
   suspended = false;
   const now = new Date().getTime();
   this.$log.debug('auto refresh resumed');
   if (now - lastRunTimestamp > pollSchedule) {
     run();
   } else {
     scheduleNextRun(pollSchedule - (now - lastRunTimestamp));
   }
 };

    }).then((searchResults: ISearchResults<ISecurityGroupSearchResult>) => {
      let result: ISecurityGroup[] = [];
      if (!searchResults || !searchResults.results) {
        this.$log.warn('WARNING: Gate firewall endpoint appears to be down.');
      } else {
        result = filter(searchResults.results, { application: applicationName });
      }

      return result;
    });

    $onInit(): void {
        this.$log.info(`[${this.name}] Initializing Controller...`);

        this.loadMessage();

        const myObs$: Observable<number> = Observable
            .from([1,2,3,4,5])
            .map(n => n * 5);

        this.subscription = myObs$.subscribe(
            n => console.log("data", n),
            e => console.error("error", e),
            () => console.log("COMPLETED")
        );
    }

  const subscription = $uiRouter.globals.start$.subscribe((transition: Transition) => {
    const details = {
      transition: transition,
      toState: transition.to(),
      toParams: transition.params('to'),
      fromState: transition.from(),
      fromParams: transition.params('from'),
    };

    $log.debug('$stateChangeStart', details);
    const success = () => $log.debug('$stateChangeSuccess', details);
    const failure = (error: any) => $log.debug('$stateChangeError', Object.assign(details, { error }));

    transition.promise.then(success, failure);
  });